81703242 has 40 divisors (see below), whose sum is σ = 187556292. Its totient is φ = 26568000.

The previous prime is 81703213. The next prime is 81703253. The reversal of 81703242 is 24230718.

It can be written as a sum of positive squares in 2 ways, for example, as 71723961 + 9979281 = 8469^2 + 3159^2 .

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 492 + ... + 12792.

Almost surely, 2^81703242 is an apocalyptic number.

81703242 is a gapful number since it is divisible by the number (82) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 81703242, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (93778146).

81703242 is an abundant number, since it is smaller than the sum of its proper divisors (105853050).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81703242 is a wasteful number, since it uses less digits than its factorization.

81703242 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12356 (or 12347 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 27.

The square root of 81703242 is about 9038.9845668637. The cubic root of 81703242 is about 433.9234257931.

The spelling of 81703242 in words is "eighty-one million, seven hundred three thousand, two hundred forty-two".